The prior art shows many different forms of leveling systems and leveling apparatus for use with various kinds of vehicles such as automobiles, campers, cranes, recreational vehicles, trucks and trailers, and the like. One type of such apparatus is associated with extensible outrigger mechanism mounted on the vehicle. Another type of such apparatus is mounted beneath the vehicle. Each type of apparatus conventionally employs one or more hydraulic cylinder units which are operable to move a ground engaging support plate or she between a vertically downwardly extending support position and a horizontally extending storage position. In some systems, the hydraulic cylinder units are pivotally movable between a vertically downwardly extending position and a horizontally extending storage position by use of one horizontally mounted hydraulic cylinder unit connected to a second hydraulic cylinder unit. In other systems, the hydraulic cylinder units are fixedly mounted in a vertical attitude and the support plate shoe apparatus is pivotally displaceable relative to the hydraulic cylinder unit during movement of he piston rod of the hydraulic cylinder unit. Such prior art systems and apparatus are disclosed in U.S. patent of Thompson U.S. Pat. Nos. 3,843,154; Hansen 3,817,493, 4,061,309 and 4,165,861; Bolard 1,783,822; Hornagold 3,901,532, 3,990,714 and 4,071,147; Tucker 2,546,203; and McCollum 1,990,047.
This invention relates to the type of leveling system and apparatus wherein the hydraulic cylinder units are fixed in a vertical attitude beneath the vehicle and the support plate shoe is pivotally movable by and relative to the cylinder unit between a horizontal storage position and a vertical support position. The support plate shoe is pivotally mounted on the piston rod so as to be pivotally actuated between the storage position and the support position by movement of the piston rod relative to the cylinder and associated cam means which are integral with the support plate mechanism and the cylinder unit